ASSOCIATED PRESSA boy holds his weapon, as he sits on guard near the site of a protest against Saudi-led airstrikes in Sanaa, Yemen, Friday, April 10, 2015. Pakistani lawmakers on Friday unanimously voted to stay out of the Saudi-led air coalition targeting Shiite rebels in Yemen in a blow to the alliance, while planes loaded with badly needed medical aid landed in Yemen's embattled capital, Sanaa, in the first such deliveries since the airstrikes started more than two weeks ago. (AP Photo/Hani Mohammed)

NEW DELHI — It's a father's worst nightmare — having to shelter his child from war and devastation.

A Yemeni aid worker's six-year-old son would ask him every day why it was suddenly so loud in Yemen.

"It's a very big wedding and we're celebrating with fireworks," he would tell his son, as they sought shelter in the basement of a building. He found it hard to explain the airstrikes, even though the crisis would form the future for Yemen's children, recounted his Indian colleague Amul Rathi, a logistician with the Médecins Sans Frontières (MSF), commonly known as Doctors Without Borders.

Rathi, who has just returned to India from Yemen where he had been deputed since mid-February this year, said things changed in Yemen drastically in a matter of days.

"I never thought the conflict would take us to the point of evacuation," he told HuffPost India. "We used to wake up to the sound of prayers, and sleep to wedding fireworks. But once the foreign airstrikes started, the sounds would keep you awake in terror, the buildings would shake."

Since March 19, more than 800 people wounded in the crisis have been brought in to MSF clinics across Yemen, some of them dead on arrival. At least 600 of them have been treated in Aden alone. Several others were unable to reach medical facilities because of access routes being blocked, or attacks on Ministry of Health ambulances. Aid workers have been killed in the process, and the injured have had to wait for hours, often lying on the street, as street fighting and sniper fire raged on, reported MSF.

"Yemen in general has beautiful people," said Rathi. "I'm really afraid and hope it stays the same." The 29-year-old aid worker described Sana'a as "quite relaxed" in early February, until things suddenly got violent. He described explosions in a mosque, and how quickly the internal fighting gave way to shelling.

Aid workers have warned of a terrible humanitarian crisis as a result of Saudi-led air campaign and battles between Shiite rebels and forces loyal to the embattled president.

Even as the MSF staff in Yemen — around 16 international aid workers and 539 locals — treated the wounded in emergency surgical units and support rooms, people fled the cities in droves.

"In Aden, there would be a big queue at the fuel station every day. Around 60 percent of the population has fled from the city already," said Rathi. It has become increasingly hard to go through the checkpoints and shift the injured to the MSF hospital in Aden, he said. Resources have been depleted, there is lesser water available; supplies are extremely low. Human resources too have taken a hit.

"There is an urgent need for medical supplies," said Rathi. "We are hoping for authorisation from Saudi Arabia," referring to a Saudi coalition full charter plane armed with supplies that is expected to come through. "If people can get evacuated, I'm sure aid can come inside."

The wounded kept coming to the hospital in droves, but aid givers were running out of supplies. Electricity become unreliable, and people were unable to cope in the extreme weather that is characteristic of the country — extremely hot in some places and the complete opposite in others, he said.

"When a situation is changing literally by the hour - it is difficult," explained an officer with MSF India. "It is a difficult situation."

Amul Rathi, 29, is an MSF India logistician who was posted in Yemen this February

"If people can get evacuated, I'm sure aid can come inside."

Aid workers too are in dilemma, said Rathi. While on one hand hand it was clear that they could make a difference with their presence in Yemen, they were worried about their own safety as well. "It is not an easy decision," he said. "Some will probably come back as soon as they get a chance. For others, it's quite difficult."

MSF reported as many as 100 injured arriving at their hospital at the same time. Several waves of such mass casualties have become the norm in Aden in the past three weeks. But this flow is ebbing — not because the number of wounded have decreased, but because they are unable to make it to the hospital.

Urgent Need For Aid, Supplies

Despite the odds, an MSF boat recently entered Aden with 1.7 tonnes of supplies to replenish the fast-depleting stocks at the hospital. A second boat, organised by the International Committee of the Red Cross, brought an additional MSF surgical team into the town, the aid group reported. Yesterday, a plane carrying 15 tonnes of medical supplies was able to enter Sana'a.

However, much more is required on the ground to treat the wounded and the remaining people in Yemen. MSF officials emphasised the need for air and water channels to remain open in order for them to safely transport medical supplies, resources.

“We are pleased that the medical supplies and staff have arrived safely, as the team at the hospital was exhausted, and there was a real risk of supply shortages,” said Marie-Elisabeth Ingres, Head of Mission for MSF in Yemen. “But with the violence continuing to cause large numbers of injured more supplies and medical staff are needed.”